JP2013195595A - Antireflection film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an antireflection film that has excellent image resolution and an antireflection property, and has excellent contrast in an image.SOLUTION: An antireflection film of the present invention comprises: an antiglare hard coat layer containing fine particles and resin; and an antireflection layer provided in this order on a transparent film. When the average value of heights in an evaluation area on the surface of the hard coat layer is zero (0), the maximum sectional height that is represented by a difference between the maximum value of height in the evaluation area and the minimum value of height in the evaluation area is 1.0 to 3.0 μm, and the average inclination angle of irregularities on the surface of the hard coat layer is 1 degree or less.

Description

  The present invention relates to an antireflection film suitably used for the surface of various displays represented by liquid crystal displays, plasma displays, and organic EL displays.

  In recent years, with the progress of multimedia, there is a remarkable spread of portable terminal devices, notebook computers, large-sized televisions and the like. Since these devices incorporate an image display device (display device), visibility (visibility) is required as the first function, but in actual use, the background is the image display unit ( Screen), the contrast is lowered and the screen is difficult to see. For this reason, the device which suppresses the surface reflection of the screen which is the cause of visibility reduction has been made.

  As a method for suppressing surface reflection, an antiglare layer containing inorganic particles such as silica and organic particles such as styrene and acrylic on a transparent film base material, forming irregularities on the display device surface, and by scattering light, An antireflection process (antiglare process) that blurs the outline by scattering a reflected image is disclosed (Patent Document 1). Further, an antireflection treatment is disclosed in which a thin film having a thickness of about the thickness of light is formed on the surface and the reflectance is reduced by the light interference effect (Patent Document 2).

JP 11-326608 A JP 2010-286657 A

  However, when antireflection processing (antiglare processing) that scatters the above-mentioned light and blurs the outline of the reflected image is performed, the resolution of the image is lowered, and sufficient visibility cannot be obtained. Further, when antireflection processing is performed to reduce the reflectance due to the light interference effect, there is no problem in the resolution (clearness) of the image, but there is a problem that sufficient antireflection properties cannot be obtained. Furthermore, when a thin film having a thickness of about the thickness of light is provided on an antiglare layer containing inorganic particles or organic particles on a transparent film substrate, sufficient effects are obtained with respect to image resolution and antireflection properties. Although it is obtained, there arises a new problem that the contrast of the image is lowered.

  Accordingly, an object of the present invention is to provide an antireflection film which is excellent in image resolution (image sharpness) and antireflection properties and excellent in image contrast.

  As a result of intensive studies to achieve the above-mentioned problems, the present inventors have laminated a hard coat layer containing at least fine particles and a resin and an antireflection layer containing a fluorine-based resin in this order on the transparent film substrate. An anti-reflection film, wherein the maximum height in the evaluation region and the height in the evaluation region when the average value of the height in the evaluation region on the surface of the hard coat layer is zero (zero) The maximum cross-sectional height represented by the difference from the minimum value is 1.0 to 3.0 μm, and the average inclination angle of the irregularities on the surface of the hard coat layer is found to be 1 degree or less to find that the above problem can be solved. . According to the present invention, an antireflection film having excellent image resolution (image clarity) and antireflection properties and excellent image contrast can be obtained, so that the visibility of the display can be improved. Further, in the antireflection film of the present invention, the transmission sharpness measured through four optical combs (width 2 mm, 1 mm, 0.5 mm, 0.125 mm) using a transmission sharpness measuring device based on JIS K 7105-1981. The total value of the images is 280% or more, and the values of the transmission sharpness measured through each optical comb are 70% or more, so that the image sharpness is high and the whitishness (white blur) of the coating film is increased. It is possible to suppress the decrease in contrast and improve the visibility of the display.

  In the antireflection film of the present invention, the fine particles have an average particle size of 1.0 to 4.8 μm, and the coating thickness of the hard coat layer is 0.5 to 1 of the average particle size of the fine particles. .5 times is preferable. The average particle size of the fine particles is more preferably 3.0 to 4.8 μm.

  Moreover, in this invention, it is preferable that the compounding quantity of the said microparticles is 0.05-3 weight part with respect to 100 weight part of said resin.

  The antireflection film has a haze value of 0.1 to 5.0%, a 60-degree specular gloss of 30% to 75%, and a 20-degree specular gloss of 10% to 50%. By setting the luminous transmittance (transmission Y value) to 94.00 or more, the effect of the present invention can be further exhibited.

  In addition, it is preferable to use a highly versatile ionizing radiation curable resin as the resin contained in the antiglare hard coat layer in a large amount at low cost.

  Moreover, as a transparent film base material used for this invention, a triacetyl cellulose film, a polyethylene terephthalate film, or a norbornene film etc. are suitable from a high visibility or a viewpoint of price, for example.

  ADVANTAGE OF THE INVENTION According to this invention, while being excellent in image resolution (image clarity) and antireflective property, the antireflection film for surface protection which was excellent in the contrast of an image and improved the visibility of a display can be provided. That is, according to the antireflection film of the present invention, the whitishness of the coating film is reduced and the contrast is improved, high transmittance, high image sharpness, image glare are suppressed, and the visibility of the display is improved. be able to.

It is a reference figure for demonstrating how to obtain | require the average inclination angle of the film surface.

Hereinafter, embodiments of the present invention will be described in detail.
The antireflection film of the present invention is an antireflection film obtained by laminating a hard coat layer containing at least fine particles and a resin, and an antireflection layer containing a fluororesin in this order on a transparent film substrate, Maximum cross-section height expressed as the difference between the maximum height in the evaluation area and the minimum height in the evaluation area when the average height in the evaluation area on the surface of the hard coat layer is zero. Is 1.0 to 3.0 μm, and the average inclination angle of the irregularities on the surface of the hard coat layer is 1 degree or less.

Here, “maximum cross-sectional height” is as defined above, but as defined in JIS B0601, it is a value calculated from the cross-sectional curve (measurement curve) of the film surface that is the object of measurement. is there. The surface of the hard coat layer containing fine particles and a resin as in the present invention has not only fine irregular shapes but also undulations. A measurement curve (usually called a cross-section curve) measured with a surface roughness measuring machine is between a waviness curve and a roughness curve.
There is a relationship of cross-sectional curve = waviness curve + roughness curve. Therefore, the “maximum cross-sectional height” in the present invention evaluates a cross-sectional curve including a “surface waviness component”. In the 2001 version of JIS, the maximum cross-sectional height is represented by the symbol “Pt”.

In addition, the above “average inclination angle” refers to the slope of a line segment that divides a cross-sectional curve (measurement curve) of the film surface to be measured at a constant interval ΔX and connects the start points of the cross-sectional curves in each section. (Inclination angle: The inclination angle is obtained by calculating the absolute value of tan ⁻¹ (determined by ΔYi / ΔX) and averaging the values (θa) (see FIG. 1), that is, the average inclination angle (θa ) Is a value defined by the following formula.

  According to the study of the present inventor, the reason for exhibiting excellent antireflection properties, image resolution, and image contrast (hereinafter sometimes simply referred to as “contrast”) according to the antireflection film of the present invention is as follows. Is guessed.

  Maximum cross-section height expressed as the difference between the maximum height in the evaluation area and the minimum height in the evaluation area when the average height in the evaluation area on the surface of the hard coat layer is zero. When the thickness is 1.0 to 3.0 μm and the average inclination angle of the irregularities on the hard coat layer surface is 1 degree or less, the surface of the undulation of the specific region or the gentle (gradual) irregularities And the refraction and scattering of light due to surface irregularities can be suppressed, so that surface haze is difficult to develop, and light loss due to light refraction and scattering can be suppressed, so that a decrease in transmittance can be suppressed. Since the phenomenon that the film becomes whitish due to scattered light on the surface of the hard coat layer is suppressed, it is considered that the film has excellent transparency and can improve image resolution and image contrast. However, although it is difficult to obtain a sufficient level of antireflection properties, the antireflection properties can be improved by providing an antireflection layer on the hard coat layer.

  If the maximum cross-sectional height on the surface of the hard coat layer exceeds 3.0 μm, the light refraction and scattering due to the unevenness of the surface is strengthened, so that the surface haze is easily developed. There is a concern about the decrease in transmittance due to the loss of light, and it becomes easy to obtain antireflection properties due to scattered light on the surface of the hard coat layer, but it is difficult to suppress the phenomenon that the antireflection film becomes whitish and turbid. Sharpness tends to decrease.

  Further, the lower limit of the maximum cross-sectional height is not particularly limited, but when the maximum cross-sectional height is less than 1.0 μm, the unevenness of the film surface becomes too small, so that the scattered light on the hard coat layer surface is small. Therefore, even if an antireflection layer is provided, it is difficult to obtain sufficient antireflection properties.

  Further, when the average inclination angle is larger than 1 degree (more than 1 degree), refraction and scattering of light due to surface unevenness is enhanced, so that surface haze is easily developed, and light loss due to refraction and scattering of light. As a result, there is concern about a decrease in transmittance, and it becomes easy to obtain antireflection properties due to scattered light on the surface of the hard coat layer, but it is difficult to suppress the phenomenon of whitish turbidity of the antireflection film. There is a problem that it tends to decrease.

Therefore, in the present invention, the maximum cross-sectional height of the surface of the hard coat layer is preferably 1.0 μm or more and 3.0 μm or less, and more preferably the maximum cross-sectional height is 1.2 μm or more and 2.5 μm. It is as follows.
The average inclination angle of the surface of the hard coat layer is preferably 1 degree or less, more preferably the average inclination angle is 0.9 degree, and still more preferably the average inclination angle is 0.7 degree or less. It is. Although there is no restriction | limiting in particular about the lower limit of the said average inclination angle, From a glare-proof viewpoint, it is preferable that it is 0.1 degree or more.
In the present invention, the “evaluation region” is a measurement region.

  Further, in the antireflection film of the present invention, transmission clearness measured through four optical combs (width 2 mm, 1 mm, 0.5 mm, 0.125 mm) using a transmission clarity measurement device based on JIS K 7105-1981. When the total value of the degrees is 280% or more and the value of the transmission definition measured through each optical comb is 70% or more, the image clarity is high and the whitishness (white blur) of the coating film Can be suppressed, contrast reduction can be suppressed, and the visibility of the display can be improved.

  The transparent film substrate that can be used in the present invention is not particularly limited. For example, polyethylene terephthalate film (PET; refractive index 1.665), polycarbonate film (PC; refractive index 1.582), triacetyl cellulose film (TAC; refractive index 1.485), norbornene film (NB; refractive index 1.525) and the like can be used, and the film thickness is not particularly limited, but about 25 μm to 250 μm is generally used. Since the refractive index of a general ionizing radiation curable resin is about 1.52, a TAC film or NB film close to the refractive index of the resin is preferable in order to increase the visibility. A PET film is preferred.

  The resin used for the hard coat layer in the present invention can be used without particular limitation as long as it is a resin that forms a film. In particular, the hard coat layer surface is imparted with hard properties (pencil hardness, scratch resistance) and hard. An ionizing radiation curable resin is preferred in that a large amount of heat is not required when forming the coat layer. In addition, the hard coat layer has a leveling agent, an antifoaming agent, a lubricant, an ultraviolet absorber, a light stabilizer, a polymerization inhibitor, a wetting and dispersing agent, a rheology control agent, and an antioxidant as long as the effects of the present invention are not impaired. An agent, an antifouling agent, an antistatic agent, a conductive agent and the like may be contained as necessary.

  The ionizing radiation curable resin is not particularly limited as long as it is a transparent resin that is cured by irradiation with an electron beam or ultraviolet rays. For example, a urethane acrylate resin, a polyester acrylate resin, and an epoxy acrylate resin It can select suitably from resin etc. Preferred examples of the ionizing radiation curable resin include those composed of an ultraviolet curable polyfunctional acrylate having two or more (meth) acryloyl groups in the molecule. Specific examples of the UV curable polyfunctional acrylate having two or more (meth) acryloyl groups in the molecule include neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, and trimethylol. Polyol polyacrylates such as propane tri (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, pentaerythritol tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A diglycidyl Epoxys such as diacrylate of ether, diacrylate of neopentyl glycol diglycidyl ether, di (meth) acrylate of 1,6-hexanediol diglycidyl ether ( A) Polyester (meth) acrylate, polyhydric alcohol, polyisocyanate and hydroxyl group-containing (meta) which can be obtained by esterifying acrylate, polyhydric alcohol and polyhydric carboxylic acid and / or anhydride and acrylic acid ) Urethane (meth) acrylate obtained by reacting acrylate, polysiloxane poly (meth) acrylate, and the like.

  The ultraviolet curable polyfunctional acrylate may be used alone or in combination of two or more, and the content thereof is preferably 50 to 95% by weight with respect to the resin solid content of the antiglare hard coat layer coating material. is there. In addition to the polyfunctional (meth) acrylate, preferably 10% by weight or less of 2-hydroxy (meth) acrylate, 2-hydroxypropyl (meth) based on the resin solid content of the antiglare hard coat layer coating. ) Monofunctional acrylates such as acrylate and glycidyl (meth) acrylate can also be added.

  Moreover, the polymerizable oligomer used in order to adjust hardness can be added to a hard-coat layer. Examples of such oligomers include terminal (meth) acrylate polymethyl (meth) acrylate, terminal styryl poly (meth) acrylate, terminal (meth) acrylate polystyrene, terminal (meth) acrylate polyethylene glycol, terminal (meth) acrylate acrylonitrile-styrene copolymer. Macromonomers such as polymers and terminal (meth) acrylate styrene-methyl methacrylate copolymers can be mentioned, and the content thereof is preferably 5 to 50 weights based on the resin solid content in the antiglare hard coat coating material. %.

  The material for forming the fine particles used for the hard coat layer in the present invention is not particularly limited. For example, silica (refractive index 1.420 to 1.460), vinyl chloride resin (refractive index 1.530), acrylic resin ( (Refractive index 1.490), (meth) acrylic resin (refractive index 1.520 to 1.530) polystyrene resin (refractive index 1.590), melamine resin (refractive index 1.650), polyethylene resin, polycarbonate resin, acrylic -Styrene copolymer resin (refractive index 1.490-1.590) etc. can be mentioned, and microparticles | fine-particles may be used independently or it is also possible to use 2 or more types together. Further, the refractive index of the fine particles is not limited, but in order to further obtain the effects of the present invention, the fine particles have a refractive index difference of 0.001 to 0 with respect to the refractive index of the resin used in the hard coat layer. It is preferable to use fine particles having a refractive index difference of 0.001 to 0.100.

  In the present invention, the coating thickness of the hard coat layer is preferably 0.5 to 1.5 times the average particle size of the fine particles constituting the hard coat layer, more preferably 0.8 to 1. .2 times. The average particle size of the fine particles is preferably 1.0 to 4.8 μm, and the average particle size of the fine particles is more preferably 3.0 to 4.8 μm in order to impart high pencil hardness.

When the coating film thickness is less than 0.5 times the average particle size of the fine particles constituting the hard coat layer, the fine particles are not fixed in the coating film, and the hardness of the coating film surface is remarkably deteriorated.
On the other hand, when the coating thickness exceeds 1.5 times the average particle size of the fine particles constituting the hard coat layer, it becomes difficult to obtain antireflection properties. The average particle diameter of the fine particles can be measured by, for example, a laser diffraction scattering method.

  Further, when the average particle size of the fine particles is larger than 4.8 μm, the hard coat layer has a thickness more than necessary when the coating thickness of the hard coat layer is set to 0.5 to 1.5 times the average particle size of the fine particles. The glare is imparted and the scattering of external light on the surface of the coating film is increased, and the surface becomes whitish due to the scattering of light, and the visibility of the display is remarkably lowered. On the other hand, when the average particle size of the fine particles is smaller than 1.0 μm, the coating film thickness must be reduced, so that the hard property is lacking.

In the present invention, the fine particles are preferably blended in the hard coat layer in an amount of 0.05 to 3 parts by weight, more preferably 0.075 to 1 part by weight, even more preferably 100 parts by weight of the resin. The blending is 0.1 to 0.5 parts by weight.
When the amount of the fine particles was less than 0.05 parts by weight with respect to 100 parts by weight of the resin, the coating thickness of the hard coat layer was set to 0.5 to 1.5 times the average particle size of the fine particles. In such a case, it becomes difficult to obtain antireflection properties. Moreover, when the compounding quantity of microparticles exceeds 3 weight part with respect to 100 weight part of said resin, a haze value will become high and the transmittance | permeability and contrast will fall.

  The hard coat layer can be formed by coating and drying a paint obtained by dissolving and dispersing the resin and fine particles in a solvent on a transparent film substrate. The solvent can be appropriately selected depending on the solubility of the resin, and may be any solvent that can uniformly dissolve or disperse at least solids (resin, fine particles, catalyst, curing agent, and other additives). Examples of such solvents include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc.), ethers (dioxane, tetrahydrofuran, etc.), aliphatic hydrocarbons (hexane, etc.), alicyclic hydrocarbons ( Cyclohexane, etc.), aromatic hydrocarbons (toluene, xylene, etc.), halogenated carbons (dichloromethane, dichloroethane, etc.), esters (methyl acetate, ethyl acetate, butyl acetate, etc.), alcohols (methanol, ethanol, isopropanol, Butanol, cyclohexanol, etc.), cellosolves (methyl cellosolve, ethyl cellosolve, etc.), cellosolve acetates, sulfoxides, amides and the like. Further, the solvents may be used alone or in combination.

  The coating method of the hard coat layer is not particularly limited, but it is easy to adjust the coating thickness, such as gravure coating, micro gravure coating, bar coating, slide die coating, slot die coating, dip coating, etc. Coating is possible by the method. In addition, the film thickness of the coated hard coat layer can be measured by observing a cross-sectional photograph of the antireflection film with a microscope or the like and actually measuring from the coating film interface to the surface.

  Examples of the fluororesin contained in the antireflection layer of the present invention include compounds having at least one polymerizable unsaturated double bond and at least one fluorine atom. Specific examples thereof For example, (1) fluoroolefins such as tetrafluoroethylene, hexafluoropropylene, 3,3,3-trifluoropropylene, chlorotrifluoroethylene; (2) alkyl perfluoro vinyl ethers or alkoxyalkyl perfluoro vinyl ethers (3) perfluoro (alkyl vinyl ether) such as perfluoro (methyl vinyl ether), perfluoro (ethyl vinyl ether), perfluoro (propyl vinyl ether), perfluoro (butyl vinyl ether), perfluoro (isobutyl vinyl ether); Perfluoro (alkoxyalkyl vinyl ethers) such as (propoxypropyl vinyl ether); (5) trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, octafluoropentyl (meth) acrylate, heptadecafluorodecyl (meth) acrylate And other fluorine-containing (meth) acrylates; These compounds can be used alone or in combination of two or more. Specific products include OPSTAR TU2205, which is marketed by JSR as an antireflection film-forming coating material.

  In the antireflection layer of the present invention, the above-mentioned ionizing radiation curable resin, organic particles, inorganic particles, leveling agent, antifoaming agent, lubricant, ultraviolet absorber, light stabilizer, polymerization prohibition, as long as the effect is not hindered. An agent, a wetting and dispersing agent, a rheology control agent, an antioxidant, an antifouling agent, an antistatic agent, a conductive agent and the like may be contained as necessary.

  Although the thickness of the antireflection layer of the present invention is usually about 80 to 120 nm, it is not particularly limited, and it is desirable to adjust appropriately depending on the use of the antireflection film. For example, it is common to adjust to 80 to 100 nm for applications in which reflectance and hue are important, and in general to 90 to 120 nm in applications in which reflectance is more important than hue. .

  In laminating the antireflection layer of the present invention, the same coating apparatus as in the case of forming the above-mentioned hard coat layer can be used, so that the viscosity and concentration suitable for each various coating apparatus, It is preferable to use an organic solvent to obtain an arbitrary coating concentration (solid content concentration). The type of the organic solvent to be diluted is not particularly limited, but ketones and alcohols are preferable from the viewpoint of compatibility with highly polar fluororesins, and alcohols may be used from the viewpoint of coating properties. More preferred. Among alcohols, it is particularly preferable to use tert-butyl alcohol (2-methylpropan-2-ol) from the viewpoint of compatibility and coatability.

  As described above, the antireflection film of the present invention is an antireflection film obtained by laminating an antiglare hard coat layer containing fine particles and a resin and an antireflection layer containing a fluororesin in this order on a transparent film. The difference between the maximum height in the evaluation region and the minimum height in the evaluation region when the average value of the height in the evaluation region on the surface of the hard coat layer is zero (zero). The maximum cross-sectional height is 1.0 to 3.0 μm, the average inclination angle of the irregularities on the surface of the hard coat layer is 1 degree or less, and 4 using a transmission sharpness measuring device based on JIS K 7105-1981. The total value of transmitted sharpness measured through two optical combs (width 2 mm, 1 mm, 0.5 mm, 0.125 mm) is 280% or more, and the transmitted sharpness value measured through each optical comb is 70%. That is more In this case, the fine particles have an average particle diameter of 1.0 to 4.8 μm, and the coating thickness of the hard coat layer is 0.5 to 1.5 times the average particle diameter of the fine particles. The amount of the fine particles is preferably 0.05 to 3 parts by weight with respect to 100 parts by weight of the resin. The haze value of the antireflection film is preferably 0.1 to 5.0%, more preferably the haze value is 0.1 to 3.5%, and still more preferably the haze value is 0.1. ~ 2.0%.

  In the antireflection film of the present invention, the 60 ° specular gloss is preferably 30% or more and 75% or less, and the 20 ° specular gloss is preferably 10% or more and 50% or less. The (transmission Y value) is preferably 94.00 or more.

  In the antireflection film of the present invention, a functional layer such as an antistatic layer can be provided on the transparent film substrate in addition to the antiglare hard coat layer and the antireflection layer containing fine particles and a resin. is there. However, if such a functional layer is provided, surface undulations may be canceled and the desired antireflection property may not be obtained. When providing a functional layer on a hard coat layer containing fine particles, The film thickness of the functional layer is desirably 0.5 μm or less.

  It is also possible to provide a functional layer under the hard coat layer. Examples of the functional layer include an easy adhesion layer and an antistatic layer for obtaining adhesion between the base material and the hard coat layer.

  Further, in the antireflection film of the present invention, on the transparent film substrate, in addition to the antiglare hard coat layer containing fine particles and the resin, the functional layer such as an antistatic layer contains fine particles in addition to the antireflection layer. When provided on the hard coat layer, if the coating thickness of the hard coat layer is set below the average particle size of the fine particles constituting the hard coat layer, the total coating thickness of the hard coat layer and the functional layer However, it is preferably 0.5 to 1.5 times the average particle size of the fine particles constituting the hard coat layer.

  The antireflection film of the present invention has a maximum height in the evaluation region when the average value of the height in the evaluation region of the surface of the antireflection film, that is, the surface of the antireflection layer is zero. The maximum cross-sectional height represented by the difference between the value and the minimum height in the evaluation region is 1.0 to 3.0 μm, and the average inclination angle of the irregularities on the surface of the antireflection layer is 1 degree or less. Is more preferable.

The following examples illustrate the invention, but are not intended to limit the invention.
The average particle size of the fine particles was measured with a laser diffraction particle size analyzer SALD2200 (manufactured by Shimadzu Corporation). The thickness of the coating film was measured by observing the cross section with a scanning electron microscope manufactured by Keyence Corporation. Unless otherwise specified, “parts” and “%” described below represent “parts by weight” and “% by weight”, respectively.

[Example 1]
<Preparation of hard coat layer paint>
To 70.0 g of toluene, 0.09 g of acrylic-styrene copolymer particles (manufactured by Sekisui Plastics Co., Ltd., average particle size 2.0 μm, refractive index: 1.525) was added and stirred sufficiently. In this solution, 27.45 g of an acrylic ultraviolet curable resin (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) and Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemical Co., Ltd.) 50 g, 0.96 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) was added, and the mixture was sufficiently stirred to prepare a paint.
<Hard coat film production>
The above-mentioned paint was applied to Fuji TAC (triacetyl cellulose film, manufactured by Fuji Film Co., Ltd.) with Meyer bar # 4 (manufactured by RDS), dried at 80 ° C. for 1 minute, and then irradiated with 350 mJ / cm ² ultraviolet light (light source) : UV lamp manufactured by Fusion Japan) and cured. The thickness of the obtained coating film was 1.6 μm.
<Lamination of antireflection layer>
After adding 0.1 g of Irgacure 184 (polymerization initiator: manufactured by Ciba Specialty Chemicals Co., Ltd.) to 18 g of methyl isobutyl ketone and 180 g of tert-butyl alcohol, the mixture was sufficiently stirred, and then an anti-reflection layer forming coating OPSTA TU2205 (fluorine-based) Resin, manufactured by JSR Co., Ltd. This paint is applied on the hard coat film obtained above using a Meyer bar, dried at 80 ° C. for 1 minute, and then irradiated with 150 mJ / cm ² ultraviolet light in a nitrogen atmosphere to prevent reflection of about 0.1 μm. A layer was obtained. Thus, an antireflection film was obtained.

[Example 2]
<Preparation of hard coat layer paint>
Example 1 except that the acrylic-styrene copolymer particles used in Example 1 were changed to melamine resin-silica composite particles (manufactured by Nissan Chemical Industries, Ltd., average particle size 2.0 μm, refractive index 1.650). A paint was prepared in the same manner as described above.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 1.6 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Example 3]
<Preparation of hard coat layer paint>
To 80.00 g of toluene, 0.02 g of acrylic particles (manufactured by Soken Chemical Co., Ltd., average particle size 1.5 μm, refractive index: 1.49) was added and sufficiently stirred. Acrylic UV curable resin (Toyo Ink Mfg. Co., Ltd., refractive index: 1.49) 18.02 g and Irgacure 184 (photopolymerization initiator, Ciba Specialty Chemicals Co., Ltd.) 1.00 g BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) (0.96 g) was added and sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 1.2 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Example 4]
<Preparation of hard coat layer paint>
The same method as in Example 1 except that the acrylic-styrene copolymer particles used in Example 1 were changed to particles having an average particle size of 3.0 μm (manufactured by Sekisui Plastics Co., Ltd., refractive index 1.525). A paint was prepared.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1 except that the Mayer bar used in Example 1 was changed to # 5. The thickness of the obtained coating film was 3.4 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Example 5]
<Preparation of hard coat layer paint>
To 70.0 g of toluene, 0.75 g of acrylic-styrene copolymer particles (manufactured by Sekisui Plastics Co., Ltd., average particle size 2.0 μm, refractive index: 1.525) was added and stirred sufficiently. 26.79 g of acrylic ultraviolet curable resin (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) and Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemicals Co., Ltd.) 50 g, 0.96 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) was added, and the mixture was sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 1.6 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Example 6]
<Preparation of hard coat layer paint>
To 70.0 g of toluene, 0.02 g of acrylic-styrene copolymer particles (manufactured by Sekisui Plastics Co., Ltd., average particle size 2.0 μm, refractive index: 1.525) was added and stirred sufficiently. In this solution, 27.52 g of an acrylic ultraviolet curable resin (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) and Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemical Co., Ltd.) 50 g, 0.96 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) was added, and the mixture was sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 1.6 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Example 7]
<Preparation of hard coat layer paint>
0.17 g of acrylic-styrene copolymer particles (manufactured by Sekisui Plastics Co., Ltd., average particle size of 4.8 μm, refractive index: 1.525) was added to 45.0 g of toluene and sufficiently stirred. In this solution, 51.12 g of an acrylic ultraviolet curable resin (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) and Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemicals Co., Ltd.) 75 g, 0.96 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) was added, and the mixture was sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 4.6 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Example 8]
<Preparation of hard coat layer paint>
0.18 g of acryl-styrene copolymer particles (manufactured by Sekisui Plastics Co., Ltd., average particle size 3.3 μm, refractive index: 1.525) was added to 65.0 g of butyl acetate and sufficiently stirred. Acrylic ultraviolet curable resin (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) 32.50 g and Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemicals Co., Ltd.) 75 g and 0.57 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) were added and stirred sufficiently to prepare a coating material.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1 except that the Meyer bar used in Example 1 was changed to # 6. The thickness of the obtained coating film was 2.9 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Comparative Example 1]
<Preparation of hard coat layer paint>
To 82.00 g of toluene, 0.18 g of acrylic-styrene copolymer particles (manufactured by Sekisui Plastics Co., Ltd., average particle size: 3.0 μm, refractive index: 1.525) was added and sufficiently stirred. Acrylic ultraviolet curable resin (Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) 15.96 g and Irgacure 184 (photopolymerization initiator, Ciba Specialty Chemical Co., Ltd.) 90 g and 0.96 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) were added and sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 1.2 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Comparative Example 2]
<Preparation of hard coat layer paint>
0.45 g of acrylic-styrene copolymer particles (manufactured by Sekisui Plastics Co., Ltd., average particle size: 3.0 μm, refractive index: 1.525) was added to 52.5 g of toluene and sufficiently stirred. In this solution, 43.69 g of an acrylic ultraviolet curable resin (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) and Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemicals Co., Ltd.) 38 g, BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) (0.96 g) was added, and the mixture was sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1 except that the Meyer bar used in Example 1 was changed to # 6. The thickness of the obtained coating film was 6.9 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Comparative Example 3]
<Preparation of hard coat layer paint>
Acrylic-styrene particles (manufactured by Sekisui Plastics Co., Ltd., average particle size 2.0 μm, refractive index: 1.525) were added to 70.0 g of toluene, and the mixture was sufficiently stirred. Acrylic ultraviolet curable resin (Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.52) 24.54 g and Irgacure 184 (photopolymerization initiator, Ciba Specialty Chemicals Co., Ltd.) 50 g, 0.96 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) was added, and the mixture was sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 1.8 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Comparative Example 4]
<Preparation of hard coat layer paint>
60.0 g of toluene, 33.0 g of acrylic UV curable resin (manufactured by Nippon Synthetic Chemical Industry Co., Ltd., refractive index: 1.520) and Irgacure 184 (photopolymerization initiator, manufactured by Ciba Specialty Chemicals Co., Ltd.) 1.50 g and 0.50 g of BYK325 (leveling agent, manufactured by Big Chemie Co., Ltd.) were added and sufficiently stirred to prepare a paint.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1. The thickness of the obtained coating film was 3.4 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

[Comparative Example 5]
<Preparation of hard coat layer paint>
The same method as in Example 1 except that the acrylic-styrene copolymer particles used in Example 1 were changed to particles having an average particle size of 6.0 μm (manufactured by Sekisui Plastics Co., Ltd., refractive index 1.525). A paint was prepared.
<Hard coat film production>
A hard coat film was produced in the same manner as in Example 1 except that the Meyer bar used in Example 1 was changed to # 10. The thickness of the obtained coating film was 5.6 μm.
<Lamination of antireflection layer>
An antireflection layer was laminated in the same manner as in Example 1 to obtain an antireflection film.

  The antireflection films of Examples and Comparative Examples produced as described above were evaluated for the following items, and the results are summarized in Tables 1 and 2 below.

(1) Maximum cross-sectional height It was measured using a three-dimensional surface roughness meter “VertScan2.0” manufactured by Ryoka System Co., Ltd. The maximum height value (P) in the evaluation region and the minimum height value (V) in the evaluation region when the average value (Ave) of the height in the evaluation region of the region cross-sectional curve parameter obtained by measurement is zero. ) To determine the maximum cross-sectional height (Pt). The measurement conditions are set as follows.
<Optical conditions>
Camera: SONY HR-50 1/3 type Objective: 10 x (10 times)
Tube: 1 x Body
Relay: No Relay
Filter: 530 white
* Light intensity adjustment: Automatically performed so that the Lamp value falls within the range of 50-95.
<Measurement conditions>
Mode: Wave
Size: 640 × 480
Range (μm): Start (5), Stop (−10)

(2) Average inclination angle The average inclination angle of the concavo-convex portions on the film surface was measured using a three-dimensional surface roughness meter “VertScan2.0” manufactured by Ryoka System Co., Ltd.
(3) Haze value The haze value was measured using a haze meter “HM150” manufactured by Murakami Color Research Laboratory.

(4) Luminous transmittance (transmission Y value)
Murakami Color Research Laboratory “integrated sphere high-speed spectral transmission measurement system DOT-3” was used, and the measurement was carried out according to JISZ8722.
Here, the luminous transmittance is obtained from Y = K∫S (λ) y (λ) T (λ) dλ. S (λ): spectral distribution of wavelength 400 to 700 nm, y (λ): color matching function, T (λ): spectral solid angle transmittance, Y: luminous transmittance.

(5) Transmission clarity Measurement was carried out using a Suga Test Instruments Co., Ltd. image clarity measuring device “ICM-1DP”. The measurement was performed using an optical comb having widths of 2 mm, 1 mm, 0.5 mm, and 0.125 mm, and the measured values at each width and the sum thereof were calculated.
(6) Glossiness (20 degrees, 60 degrees)
Using a gloss meter (GM-3D) manufactured by Murakami Color Research Laboratory, apply a black vinyl tape (Nitto Vinyl Tape, PROSELF No. 21 (wide)) to the opposite side of the coating and measure the glossiness at 20 or 60 degrees. did.

(7) Pencil hardness Using HEIDON 14 manufactured by Shinto Kagaku Co., Ltd., it was carried out according to JIS K 5400.
(8) Glitter Each anti-glare film was layered on a liquid crystal display (LCD) having a resolution of 150 ppi that was displayed in green on the entire surface, and the degree of occurrence of glittering screen was visually evaluated. In addition, a clear type hard coat film which does not generate glare was previously set on the LCD surface. The case where there was no glare and the case where the glare was slight was designated as “◯”, and the case where the glare was large and the visibility deteriorated was designated as “X”.

(9) White blur, whitish White blur due to reflection of external light is used as an index of contrast, and black vinyl tape (Nitto Vinyl Tape, PROSELF No. 21 (wide)) is pasted on the opposite side of the coating. The black density was measured with a total. 2.15 or more is “◯”, 2.10 or more and less than 2.15 is “Δ”, and less than 2.10 is “x”. In addition, the whitishness of the coating film due to transmitted light is that light diffuses in the film due to internal haze when the white fluorescent lamp is viewed through an anti-glare hard coat film with the coated surface facing the observer. The state in which the coating became whitish was visually evaluated. Those with no whiteness and slight whiteness were indicated with “◯”, those with a slight whiteness were indicated with “△”, and those with a white coating film were indicated with “X”.

(10) Anti-glare property Anti-glare property is obtained by reflecting 10 lines drawn at 1mm width on the coated surface of the anti-reflection film, and setting the line width through the anti-reflection film with the coated surface facing the observer. The state where the line width was blurred and difficult to see due to light scattering when viewed was visually evaluated. “◯” indicates that the line width cannot be recognized, and “X” indicates that the line width can be recognized.

  As is clear from the results in Tables 1 and 2 above, a hard coat layer containing fine particles and a resin and an antireflection layer containing a fluororesin are laminated in this order on a transparent film substrate. In each of Examples 1 to 8 in which the maximum cross-sectional height in the evaluation region on the surface of the coat layer is 1.0 to 3.0 μm or less and the average inclination angle is 1 degree or less, both the image resolution and the antireflection property are achieved. An antireflection film having excellent image contrast and excellent image contrast was obtained.

  On the other hand, although containing fine particles, the maximum cross-sectional height in the evaluation region of the surface of the antiglare hard coat film is outside the range of 1.0 to 3.0 μm, In Comparative Example 3 in which the number of added parts is large, Comparative Example 4 in which fine particles are not added, and Comparative Example 5 in which the average particle diameter is larger than the desired range of the present invention, all have good image resolution and antireflection properties. The image contrast could not be satisfied at all.

Claims (7)

  An antireflective film in which a hard coat layer containing at least fine particles and a resin and an antireflective layer containing a fluorine-based resin are laminated in this order on a transparent film substrate, and the evaluation area of the surface of the hard coat layer The maximum cross-sectional height represented by the difference between the maximum height value in the evaluation region and the minimum height value in the evaluation region when the average value of the inner heights is zero (zero) is 1.0-3. The average inclination angle of the irregularities on the surface of the hard coat layer is 1 degree or less, and four optical combs (width 2 mm, 1 mm, 0 .2 mm) using a transmission sharpness measuring device based on JIS K 7105-1981. 5 mm, 0.125 mm), and the total value of transmission clarity measured through each optical comb is 280% or more, and the transmission clarity value measured through each optical comb is 70% or more. .   The fine particles have an average particle size of 1.0 to 4.8 μm, and the coating thickness of the hard coat layer is 0.5 to 1.5 times the average particle size of the fine particles. Item 2. The antireflection film according to Item 1.   The antireflection film according to claim 1 or 2, wherein the fine particles have an average particle size of 3.0 to 4.8 µm.   The antireflection film according to any one of claims 1 to 3, wherein the compounding amount of the fine particles is 0.05 to 3 parts by weight with respect to 100 parts by weight of the resin.   The antireflection film has a haze value of 0.1 to 5.0%, a 60-degree specular gloss of 30% to 75%, and a 20-degree specular gloss of 10% to 50%. The transmittance (transmission Y value) is 94.00 or more, and the antireflection film according to any one of claims 1 to 4.   The antireflection film according to claim 1, wherein the resin contained in the hard coat layer is an ionizing radiation curable resin.   The antireflection film according to claim 1, wherein the transparent film substrate is a triacetyl cellulose film, a polyethylene terephthalate film, or a norbornene film.

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